circumstances to record a save in MLB?

Answer 1

Let's just quote the relevant parts of Rule 10.19, it's not very long and written clearly.

MLB 10.19, Saves For Relief Pitchers:
The official scorer shall credit a pitcher with a save when such pitcher meets all four of the following conditions:
(a) He is the finishing pitcher in a game won by his team;

(b) He is not the winning pitcher;

(c) He is credited with at least a third of an inning pitched; and

(d) He satisfies one of the following conditions:
(1) He enters the game with a lead of no more than three runs and pitches for at least one inning;
(2) He enters the game, regardless of the count, with the potential tying run either on base, or at bat or on deck (that is, the potential tying run is either already on base or is one of the first two batters he faces); or
(3) He pitches for at least three innings.

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Most saves are either type (d)(1) or (d)(2).

Answer 2

I belive its: If you are brought in with 1 inning to go and you are ahead by 3 runs or less, you get the save if your team wins.

And I believe you can have a 6 run lead or less if you go 2 innings of closing to capture the save.

Answer 3

If there are as many at bats for the oppossing team as their are runs to be scored up to 4 run lead I believe. Also, if a pitcher comes in, in a situation that he did not cause (guys on base were from another pitcher) as long as the tieing run is on deck it is considered a save.

Answer 4

less than 3 runs or with the tying/winning run on base/at bat